Please refer to FIG. 1, which is a schematic view showing a conventional lens structure. The conventional lens structure includes a lens device 10, a circuit board 13 and a sensor 14. Further, the lens device 10 includes a lens tube 11 and a lens base 12, and the sensor 14 is mounted on the circuit board 13. The lens tube 11 further includes an end having a receptacle portion 15 for containing the sensor 13, and the end of the lens tube 11 is mounted on the circuit board 13. Moreover, the circuit board 13 is further used for mounting the lens base 12 thereon.
According to the general imaging theory, a plurality of reflected lights from an object would be received by the lens device 10, and a plurality of focused lights would be generated within the lens device 10, i.e. the reflected lights are focused on the sensor 14, by a plurality of lenses of the lens tube 11. Further, the sensor 14 could convert these focused lights into various digital signals. Then, these digital signals would be transferred to other devices by the circuit board 13 to process the following steps for showing an image or storing the image.
However, various researches for the arrangement between the lens device and the lenses have been developed by the optical lens manufacturers to provide digital images with a better definition and introduce more functions, such as an auto-focus function, a macro-mode photo function, multi-apertures, a zoom lens with a mechanical shutter and zoom ratio, etc. Such researches not only involves complex optical, optomechanical and electrical control techniques, but the expense therefor is very high. Therefore, the price for the optical lens, i.e. the lens device 10, usually is very expensive.
Besides, these techniques, such as adjustments for the alignment, the position or the focus between the optical lens and the sensor, are also quite important, and the image quality would be enhanced according to the above adjustments. In addition, the optical lens manufacturers often suggest that the size or standard of the sensor should be chosen according to the type of the optical lens. Further, these optical lenses would be used in various products, such as a digital camera, a visualizer or a digital video camera. Accordingly, most product manufacturers often accept the optical lens manufacturers' suggestion to adopt a designated size or standard of sensor in a designated optical lens.
While the product with a particular standard or size of sensor is produced by the product manufacturer, the corresponding optical lenses must be particularly provided by the optical lens manufacturer. However, the charge for re-designing and producing the particular optical lens is very costly. Therefore, the manufacturing cost and the price for the products may go up quite substantially and there will be no market for these products.
Therefore, the purpose of the present invention is to develop a lens assembly to deal with the above situations encountered in the prior art.